How would you advise students in the example "1-(x+2-3)"? Can I tell them to drop the parentheses and reverse the signs of each term? Is the explanation that if we change the subtraction to an addition we can use the associative property of addition? Are there alternative methods? I've seen one book that suggests solving it as follows:1-(x+2-3) => 1+ -1(x+2-3)=> then solve -1(x+2-3)- -1(x)+-1(2)- (-1)(-3)but this seems a bit confusing to me.Any suggestions?Thanks, --John